Answer:
f(n)= 5 · 4
Step-by-step explanation:
You use the explicit formula for geometric sequence. The five is the firat term and is placed correctly. The 4 is the rate of change, because if you multiply 5 by 4 you get 20 and so on.
Answer:
B
Step-by-step explanation:
x(2x + 3)
Expand the brackets.
x(2x)+x(3)
Multiply the terms.
2x² + 3x
The answer is 2x² + 3x.
Answer:
54.5
Step-by-step explanation: